Method of refrigeration



S. C. CARNEY May 21, 1929.

METHOD oF RERIGERATIQN Filed Oct. 28 1925 Patented May 21, 1929.-

UNlTl-:D STATES.

OF TULSA, OKLAHOMA, ASSIGNOR T SHELL PETROLEUM COB PORATION, A CORPORATION OF VIRGINIA.

SAMUEL C. CARNEY,

PATENT OFFICE.

METHOD OF REFRIGERATION.

Application filed October 28, 1925. Serial No. 65,346.

This invention relates to a method of refrigeration.

It has been determined that hydrocarbon mixtures comprising blends of pro ane, ethane or other similar light hydrocar ons, when liquefied and expanded directly in water or in certain other liquids, for cxample, heavy petroleum products used as lubricants, the li uid may `be artially 1o frozen or congeale and that the rozen or congealed bodies may be withdrawn from lthe excess liquid.

It has also been determined that when a hydrocarbon refrigerant of the character mentioned are mixed with water, preferably in the presence of a partial vacuum, it is only very slightly soluble in the water, even at a temperature of approximately 32o F., and that the small amount of absorption by water of such hydrocarbons, particularly when pure, impart practically no taste or odor to the ice and are not deleterious or harmful, so that ice for commercial purposes may be frozen in this manner. It is an object of the invention to providel a method whereby a hydrocarbon refrigerant of the general character mentioned in a liquid state may be mixed with water or other suitable liquid in a chamber and thereby freeze lthe liquid. y

In the drawing there is illustrated a form of apparatus suitable for carrying out the method of the invention, although it will be understood that the invention may be practiced in various other ways.

By reference to the following disclosure, taken in connection with the accompanying drawing, the advantages as well as the additional a lications of the process may be 4o readily un' erstood.

In the drawing, Fig. 1 is a plan view 'of .the apparatus, and Fig. 2 is a vertical section through theapparatus. l

t The apparatus comprises a chamber preferably having a cylindrical side wall 1. a convex bottom 2, and a concave head 3 forming together an air tight container. The chamber and the pi es connected thereinto are preferably insu ated by a covering 5o 4.- of any suitable insulating material. Within the chamber and running transversely near one side thereof is a perforated partltion 5. This partition 5 extends upwardly from the bottom wall of the chamber to a point above the normal liquid level maintained in the tank. s

It is desirable that means be provided to create a partial vacuum in the chamber 1 s and the best results are obtained at an absolute pressure of five pounds, or less, when the process is used for making ice.

An inlet pipe 6 enters the bottom of the chamber, the opening of the pipe being disposed inwardly of the partition 5, and an overilow pipe 7 enters the chamber 1 at a point spaced upwardly from the bottom of the chamber. A suction pump 8 withdraws the liquid through the pipe 7 and discharges it into the bottom of the chamber through the pipe 6. The pipe 6 is arranged so that 70' the flow of liquid from the pipe strikes the circular inner wall of the chamber 1 at a tangent, thereby! imparting to the liquid in the chamber a rotary motion, the effect of which is to drive the frozen or congealed bodies of the liquid toward the center of the chamber.

The hydrocarbon refrigerant is supplied to the bottom chamber through a su ply passagel 9 controlled by a valve 10, w ere it is directly mixed with the incomin liquid and discharged with it into the c amber through the pipe 6. The apparatus is adjusted so that at all times there will be a substantial excess of the liquid inthe 'chamber 1, and so that the liquid level will be maintained approximately uniform at the oint illustratedinFig. 2 of the drawing.

his is accomplished by a liquid level device 11 connected with a valve 12 in a sup ly pipe 13 through which the water or other liquid is supplied directly to the pipe 7 to re lace the liquid in frozen state that is withdrawn from the chamber 1.

. It will be understood that the mixture of tion of the refrigerant while it is submerged v in the liquid and that, as a result, a reevaporation taires place, the frozen particles or bodies of the liquid rising to the top of the liquid level of the excess liquid in the chamber.

The partition wall 5 acts as a baffle to prevent the frozen bodies from clogging the throat of the pipe 7, so that there may be a free flow of the excess liquid through the pipe for re-treat1nent- By properly balancing the pressure in the chamber 1 substantially all of the refrigerant may be evaporated in the presence of the liquid. Whatever unevaporated refrigerant there may be while it remains in the liquid state will float on the excess liqui'd and Will be withdrawn through the pipe 7 thereby preventing any Waste of the refrigerant and obtaining the full refrigerating effect thereof.

The incoming mixture of the refrigerant and liquid is prevented from freezing and clogging the inlet pipe 6 b'y the excess of the liquid and also by the action of the pump. An part of the refrigerant that vaporizes a ter passing through the liquid is trapped in and withdrawn from the upper part of the chamber l through the outlet passage 14, through which it may be introduced into any suitable recovery system, it being understood that the outlet 14 is connected with the recovery system to make the interior of the chamber air tight so that a partial vacuum may be maintained dur'- ing the operation of the apparatus.

he frozen bodies of the liquid, after accumulating upon the top of the excess liquid in the chamber 1 and being forced to the central part of the chamber through the whirling action of the liquid, are continuously withdrawn by a conveyor system 15, a portion of which is illustrated in the drawing, said conveyor system being more fully illustrated and described in my copending application Serial No. 59,796.

It is obvious that the foregoing process provides ka continuous method for the production of ice and other frozen bod-ies, and that by withdrawing the separate bodies from the chamber through suitable compression apparatus, cakes of ice or other congealed liquids may be made in commercial form.

When the process is used to congeal liquids other than water, for example, lubricating oils or the like, it is desirable that a brine solution or other liquid of low freezing point, which will not mix with the oil, should be used to supply the excessive liquid in the chamber 1. The congealed bodies of the liquid under treatment will rise to the level of this carrying liquid, from which they may be withdrawn in the manner above described. f. It is desirable to carry on. the refrigera- @masse tion of the liquids in the presence of a partial vacuum in the chamber 1, particularly where the process is used in the manufacture of ice, for the reason that the reduced pressure reduces the solubility of the refrigerant in the water. li/loreovf.` the reduced pressure permits a certain evaporation of the Water in the chamber augmenting the refrigerating action. ft will be understood, however, that the maintenance of a pressure below atmospheric will not in all cases be necessary and the pressure may be varied to some extent dependent upon the liquid under treatment.

It is obvious also that the method may be carried on economically as the entire eect of the expanding hydrocarbon refrigerant is utilized.

I am aware that the invention may be modified in certain particulars without departure from the spirit and scope thereof. I do not limit myself unessentiall but what I claim and desire to `secure by etters Patent is 1. A method of freezing liquids, which includes supplying a mixture of liquid hydrocarbon to an excess of liquid to be frozen in a chamber, maintaining a partial vacuum in said chamber, eva orating a part of the hydrocarbon liquid, wlthdrawing the unevaporated liquid refrigerant from the chamber, and drawing the frozen bodies of the liquid from the excess of liquid in the chamber.

2. The method of freezing liquids, which consists in supplying a mixture of liquid hydrocarbon to an excess of liquid to be frozen in a chamber, maintaining a partial vacuum in said chamber, evaporating a part of the hydrocarbon liquld, withdrawing the unevaporated liquid refriger'ant from the chamber, withdrawing the frozen bodies from the excess of li uid in the chamber, and

separately withdrawing the vapor of the refrigerant from the' chamber'.

8. A method of refrigeration which consists in maintaining in a chamber a body of liquid to be frozen, withdrawing and returning the liquid belowl the liquid level maintained in the chamber, suppl ing to the returning liquid a quantity o refrigerant, evaporating the liquid refrigerant from the mixture so formed to freeze a portion of the liquid, and withdrawing the lfrozen portion of the liquid from the chamer. l

4. A methd of refrigeration which consists in supplying a quantity of liquid to be frozen to a chamber, injecting a mixture of refrigerant and li uid below the level of the li uid in the cham er, evaporating the liquid re rigerant from the mixture so formed to 'freeze a portion of the liquid, and withdrawing the frozen portion of the liquid from the chamber.

liquid 5. A continuous method of making ice which consists in `suppl water to a vclosed cham the chamber said feed including a mg ja quantity of\ r, malntaining' a feed below the water level of the water inmixture a refri rant, evaporating the the frozen bodies of ice from the excess o water in the king ice which consists in supplying a quantity of 10 water to a closed chamber, mamtaining a feed below the water'level of the water in the chamber, said feed including a refrigerant liquid, evaporating the refrigerant, and withdrawing the frozen bodies of ice 15 from the excess of water in the chamber.`

SAMUEL c. GARNEY. f 

